Arcless receptacle and plug connecter



Aug. 9, 1932. E. c. HELLWIG 1,870,625

ARCLESS RECEPTACLE AND PLUG CONNECTER I Filed Jan. 10, 1951- 4Sheets-Sheet 1 INVENTOR Z772 afizzzu z y ATTORN EYS Aug. 9, 1932. E. c.HELLWIG ARCLESS RECEPTACLE AND PLUG CONNECTER Filed Jan. 10, 1931 4Sheets-Sheet 2 llf lllllllllllt I (Tl/1170 10711111! lNVE NTOR CTfieZZWE q ATTORNEY-5 Aug. 9, 1932. E. c. HELLNIG ARCLESS RECEPTACLE ANDPLUG CONNECTER LEEQQZS Filed Jan. 10, 1931 4 Sheets-Sheet 3 I .ifezzwINVENTOR ATTORNEYS Aug. 9, 1932. E. c. HELLWIG ARCLE SS RECEPTACLE' ANDPLUG CONNECTER Filed Jan. 10, 1931 4 Sheets-Sheet 4 INVENTOR ATTORNEYSPatented Aug. 9, 1932 UNITED STATES PATENT OFFICE EMIL C. HELLWIG, 0FAURORA, ILLINOIS, ASSIGNOR TO THE PYLE-NATIONAL CONE-- PANY, OF CHICAGO,ILLINOIS, A CORPORATION OF NEW JERSEY ARCLESS RECEPTACLE AND PLUGCONNECTER Application filed January 10, 1931.

My invention relates to improvements in arcless receptacles and plugconnecters and has for one object to provide in connection with aterminal plug and receptacle, means whereby one electric circuit may beplugged into another electric circuit and accomplish the transmission ofpower without the clos- The present invention contemplates a con--necter for an electrical extension so made that no spark or are iscreated on connecting or disconnecting the plug member. This makes itsuitable for combustible atmosphere such as in powder plants, Duco paintplants, grain elevators, oil refineries and the like.

The connecter is made with a transformer with a primary always incircuit with the line, consequently the extension is from the secondarywith a reduced voltage of say 32 volts. The utilization of the 82 boltextension line is possible without changing the standard voltage 01 110of the main circuit and with which the connecter is installed.

The low voltage in the extension makes it possible to use the same withsafety. The low voltage extension circuit not being grounded makes itdoubly safe from electrical shock should the installation of theextension be defective. Furthermore, there is less chance of an are orspark through poor installation should any part of the extension circuitcome in contact with some grounded object.

The primary is provided with a keeper which closes the magnetic circuittherethrough thus preventing burning out of the core and the preventionof the creation of excessive heat. inserted in the socket containing theprimary and turned to lock the pipes together, such turning moves thekeeper out of the path of the magnetic plug.

My invention is illustrated more or less dia- Oncethe plug member isSerial No. 507,821.

grammatically in the accompanying drawings, wherein- Figure l is a sideelevation of the assembled plug and socket;

. Figure 2 is a longitudinal section through the socket and plugassembled to form a transformer;

Figure 3 is a section through the socket showing the cover closed-Figure 4 is a section through the plug at right angles to the section ofFigure 2 showing the position it assumes as it is about to be engaged bythe socket;

Figure 5 is a front elevation of the socket with the cover open beforethe plug has been inserted;

Figure 6 is a front elevation of the plug;

Figure 7 is a detail perspective of the receptacle core and coilassembly;

Figure 8 is a detail perspective of the plug core and coil assembly;

Figure 9 is a perspective of the socket cover showing diagrammaticallyits relation with the coil keeper;

Figure 10 is a perspective of the locking ring.

Like parts are indicated by like characters throughout the specificationand drawings.

A is a socket having a supporting flange A by which the socket may bemounted on any suitable support; a conduit A leads from the socket andcontains power conductors A The socket is bell mouthed as indicated at Aand the mouth is closed by a cover A having hinge arms A pivoted onbracket arms A on the housing. A is a spring tending to hold the coverclosed- A is a latch tongue on the cover adapted to cooperate with theplug to hold it in proper working position. A is the plug adapted topenetrate the bell mouth A of the socket A. This plug has a notch A toreceive the locking tongue A to assist in holding the socket and plug inWorking relation. A is a packing gland through which the conductor wiresA extend to any suitable lamp or motor or any other electric machine ordevice which is to be supplied with power from the socket through theplug.

The plug A itself is hollow and contains a coil and core which willsubsequently be described. The same thing is true of the socket.Contained within the bell mouth A of the socket is a locking ring A. Itis slotted as at A. On one side of the slot is a stop A, on the otherside of the slot a cam surface A" terminating in a notch A, on the otherside of which is a stop A The end of the socket has a lug A. When thetwo are to be assembled, the plug is trust into the socket, the lug Aentering from the back toward the front, as viewed in Figure 10, ofthe'holding ring through the slot A. The plug is then rotated causingthe lug A to travel along the cam surface A" until it engages the notchA, further movement being prevented by the stop A Rotation of the plugin the wrong direction being prevented by the stop A Referring now tothe socket, it will be noted that it contains a core B. This core ismade of laminated iron and has arms B B B joined by a central base andcontaining a primary coil B excited by the wires A This core is mountedin a carrier sleeve B A spring B is introduced between the sleeve B. andthe bottom of the socket and the sleeve is slotted at B and the slot isengaged by a guide pinB to prevent rotation of the carrier, limit itsoutward movement while leaving it free to be forced inwardly as thespring is compress-ed. The core and coil assembly is held in the carrierby the central screw B", which screw extending through the core androtatable in the core and carrier has on its end a rotatable keeper B Inthe position shown in Figures 3, 5 and 7 the keeper is in the plane ofthe members I5 13 B and is in contact with all three of them, therebyclosing the magnetic circuit through the core elements. The purpose ofthis is to reduce to a mlnimum the reluctance "so as to preventresistance to currentfflow in the primary coil when current is not beingsupplied to and through the plug. Referring to Figures 3 and 9, it willbe noted that the cover A has a pair of inwardly projecting lugs 13.These lugs straddle the keeper B and when the cover is down holds thekeeper in the position shown in Figures 3, 5 and 7, there being a slighttendency of the magnetic field to cause rotation of the keeper. This isprevented by this engagement of the keeper with the lugs on the cover.

Referring now to the plug, it will be noted that the plug contains acore piece C comprising arms C C C joined-by a central back piece asindicated and having associated with them a secondary coil C incommunication with the wires A Projecting from the face of the corepiece C at a point removed from the center thereof is a pin C This pinis adapted to penetrate a hole C in the keeper B The device is put intooperation by lifting up the cover, then inserting the plug. When theplug is inserted with the lug A in the slot A the pin C penetrates thehole C, then when the plug is rotated through 90 to'bring the lug A intoengagement with the notch A the eccentric pin C engaging the hole Ccauses the keeper to rotate into the position it is shown assuming inFigure 2. That is a position wherein the keeper is out of contact withmembers B and B and in contact only with the pole piece 13 I then havean arrangement of parts such as is shown in Figure 2 with the polepieces B C B C and B C abutting one another, the keeper 13 forming forthe time in this connection a part of the pole piece B Under thesecircumstances the device opcrates just as any other transformer andtransformed current passes through the wires A being generated by theexciting eifect of the transformer field on the secondary coil. Thecover engaging the notch in the plug furnishes an additional means forlocking the plug against rotation and withdrawal.

It will be obvious that the relation be tween .the primary and secondarycoils may be anything desired, the transformer may be a step down orstep up transformer as the case may be. It may be desirable to use it toincrease or decrease the voltage or to give substantially the samevoltage.

I claim:

1. In an electric plug and socket, core elements and coils mountedineach and means for locking them removably together to maintain the coreelements and coils in working relation to form an electric transformer,and means associated with the primary coil and operative only when theplug and socket are not locked together for closing a magnetic circuitthrough the core elements associated with such coil.

2. In an electric plug and socket, core elements and coils mounted ineach and means for locking them removably together to maintain the coreelements and coils in working relation to form an electric transformer,means associated with the primary coil and operative only when the plugand socket are not locked together for closing a magnetic circuitthrough the core elements associated with such coil, said meanscomprising a keeper pivotally mounted on the core elements and adaptedto be rotated into and out of magnetic circuit closing position.

3. In an electric plug and socket, core elements and coils mounted ineach and means for locking them removably together to maintain the coreelements and coils in working relation to form an electric transformer,means associated with the primary coil for closinga magnetic circuitthrough thecore elements associated therewith, and means as sociatedwith the secondary coil and core elements for automatically displacingsaid first mentioned magnetic circuit closing means when the plug andsocket are in working relation.

4. In an electric plug and socket, a coil and a core element comprisinga plurality of pole pieces joined at one end and projecting forwardly ingeneral parallelism with the axis of plug and socket respectively, andmeans for removably locking the plug and socket in'working relation withthe pole pieces of one abutting and 'in line with the pole pieces of theother, and a keeper pivoted on one of the'pole pieces associated withone of the coils and mounted for rotation into and out of engagementwith another pole piece associated therewith.

5. In an electric plug and socket, a coil and a core element comprisinga plurality of pole pieces joined at one end and projecting forwardly ingeneral parallelism with the axis of plug and socket respectively andmeans for removably locking the plug and socket in working relation withthe pole pieces of one abutting and in line with the pole pieces of theother, a keeper pivoted on one of the pole pieces associated with one ofthe coils and mounted for rotation into and out of engagement withanother pole piece associated therewith, and means associated with theother coil for engaging such keeper and rotating it out of engagementwhen the pole pieces except the one upon which it is pivoted when theplug and socket are in working relation. 6. In an electric plug andsocket, a coil and a core element comprising a plurality of pole piecesjoined at one end and projecting forwardly in general parallelism withthe axis of plug and socket respectively, means for removably lockingthe plug, and socket in working relation with the pole pieces of oneabutting and in line with the pole pieces of the other, a keeper pivotedon one of the pole pieces associated with one of the coils and mountedfor rotation into and out of engagement with another pole pieceassociated therewith, and means associated with the other'coil forengaging such keeper and rotating it out of engagement with the polepieces except the one upon which it is pivoted when the plug and socketare in working relation, the means for locking the plug and socket inworking relation comprising a cam and latch operative only upon relativerotation of plug and socket.

7. A transformer comprising a ,primary and a secondary coil, a coreassociated with associated with a cam and notch and a member carryingthem and slotted to permit initial entry of the lug and to requirerotation of the lug with respect to the member before it engages withthe notch in locked position, and a keeper mounted on one of the polepieces adapted to. be engaged by the other and rotated as the polepieces come into locked working relation to move the keeper intoinoperative position.

9. A transformer comprising a primary coil and a secondary coil, a coreassociated with each comprising a plurality of pole pieces joinedtogether at one end only, means for removably locking the pole piecestogether in abutting relation to complete the magnetic circuitassociated with the two coils, the

locking means comprising a lug associated with a cam and notch and amember carrying them and slotted to permit initial entry of the lug andto require rotation of the lug with respect to the member before itengages with the notch in locked position, the keeper being adapted tobe rotated by relative rotation of the pole pieces into such positionthat it bridges the gap between the pole pieces when the two coils areseparated.

10. A transformer connecter including a plug member and a socket member,a primary winding in the socket member, a secondary winding in the plugmember, means for removably locking together said plug and said socket,means associated with the primary winding for closing the magneticcircuit therethrough when the plug is disconnected, said means beingrendered ineffective for closing the magnetic circuit through theprimary when said plug is applied to said socket.

Signed at Chicago, county of Cook and State of Illinois, this 8th day ofJanuary,

EMIL C. HELLWIG.

each comprising a plurality of pole pieces joined together at one endonly, means for removably locking the pole pieces together in abuttingrelation to complete the magnetic circuit associated with the two coils,the locking means comprising a lug associated with a cam and notch and amember carrying them and slotted to permit initial entry of the lug andto require rotation of the lug with re-

